1. Field of the Invention
The invention relates to a mounting device for mounting an electrical device on open trunking. This kind of trunking has a substantially U-shaped profile in cross section. Its continuous longitudinal open side is designed to be closed off by one or more lengths of a cover section nesting over the trunking.
To this end, the trunking includes two parallel grooves defined along respective longitudinal edges of its open side. All the components are obtained by extruding or drawing a material, typically a semi-rigid plastics material, aluminum or another material, for example. They can also be bent to shape from sheet metal.
2. Description of the Prior Art
One prior art mounting device for mounting an electrical device that can be fitted to the trunking itself is substituted for the cover section at a selected location on the trunking. The electrical devices that can be installed in this way are typically socket outlets, telephone jacks, switches, etc.
For example, published French patent No 2 666 479 describes a mounting device of the above kind forming a box in which the electrical device is housed.
When installing wiring, it is desirable for the support on which the electrical device is mounted to be movable longitudinally along the trunking, the final location of the electrical device being determined subsequently.
The invention relates to a two-part mounting device for mounting the above kind of electrical device, one part receiving the electrical device and the other part forming a skirt which covers and surrounds the first part and closes off the trunking locally.
The basic idea of the invention is to immobilize the first part of the mounting device, containing the electrical device, in the longitudinal direction of the trunking, at installation time, by forcibly nesting the second part of the mounting device, forming the skirt.
To be more specific, the invention therefore provides a mounting device on open trunking of the kind having two parallel grooved portions defining grooves along respective longitudinal edges of its open side, said mounting device including a support for said electrical device provided with interconnecting means, also referred to as nesting means, adapted to cooperate with said trunking and a skirt conformed to be fixed to said support, made from a semi-rigid material and having two inturned or bent longitudinal edges adapted to engage in respective grooves of said trunking and conformed to engage forcibly in said grooves to immobilize said electrical device support longitudinally on fixing said skirt to said support.
In the foregoing definition of the invention, the electrical device support can take the form of a simple frame which preferably includes means for fixing the electrical device; it can also take the form of a box that can be integrated inside the trunking and electrically insulates the electrical device in the trunking. The box can be in one piece with a frame part, the combination constituting said electrical device support and providing the fixing.
In another embodiment, the electrical device support has a part in the form of a frame to which can be attached one or even two insulative housings constituting at least part of a box that can receive the electrical device. The housing can consist of one half-box assembled to the rear face of the frame, for example, or even two complementary half-boxes constituting a complete box. The top part of the support forming the frame of the support can have significantly larger dimensions than the box itself so that it can be mounted on wider trunking, possibly incorporating a plurality of partitions.
A support-skirt assembly is also feasible in which superposed openings exposing the front face of the electrical device are eccentric to the axis of the trunking.
There are various ways to stabilize the longitudinal position of the electrical device support when fixing the skirt.
One way is for the outside surfaces of the two bent longitudinal edges of the skirt to be spaced by a distance corresponding to (in fact slightly greater than) that between the inside surfaces of the outside edges of the grooves of the trunking. This distance can therefore be such that the bent longitudinal edges, on the one hand, and the outside edges, on the other hand, come into rubbing contact when fitting the skirt.
In this case, forcibly nesting the skirt over the electrical device support spreads the lateral walls of the trunking, which clamps the skirt and therefore the electrical device support. Conversely, the inside surfaces of the two bent longitudinal edges of the skirt can be spaced by a distance corresponding to (in fact slightly less than) that between the outside surfaces of the inside edges of the grooves of the trunking, this distance being such that the bent longitudinal edges, on the one hand, and the inside edges, on the other hand, come into rubbing contact when fitting the skirt.
In this case, the clamping which immobilizes the skirt and the electrical device support is operative between the inside edges of the grooves. A combination of the above two clamping arrangements is also feasible.
In particular, the surfaces of the two bent longitudinal edges previously cited can carry raised patterns cooperating with the corresponding edges of the grooves. The patterns are preferably defined on the inside surfaces of the two bent longitudinal edges. They can take the form of parallel ribs substantially perpendicular to the longitudinal direction of the bent longitudinal edges of the skirt. When the skirt is fitted, the patterns are deformed and slightly crushed on coming into contact with the facing edges of the grooves.
According to another advantageous feature, the longitudinal sides of the electrical device support include elastic hooks and spaced projecting rims, respectively adapted to bear on opposite sides of inside longitudinal walls defining the two grooves of this kind of trunking. The hooks are defined between cut-outs in the longitudinal lateral surfaces of the support. The cut-outs impart some elasticity to the hooks, enabling them to retract inwards on forcibly nesting the electrical device support. To allow this, in the absence of the skirt, the electrical device support can slide even though it is nested over the trunking.
The skirt advantageously includes abutments which abut the hooks to immobilize them when they are interengaged with the inside longitudinal walls defining the two grooves of the trunking previously cited. This avoids unintentional xe2x80x9cunclippingxe2x80x9d when withdrawing a plug, entailing the application of some traction force. The electrical device support includes windows adjacent the hooks and in which said abutments engage at the time of assembling the skirt and the electrical device support. The electrical device support and the skirt have clipping means, known in the art, by means of which they can be fixed together when in position on the trunking, this immobilizing the electrical device support longitudinally, as explained above.
According to another advantageous feature, which is known in itself, at least one transverse lateral face of the electrical device support carries projecting assembly members conformed to cooperate with complementary assembly members of a similar electrical device support, the two electrical device supports being mounted and fastened side by side in the trunking. In this way a plurality of mounting devices in accordance with the invention can be disposed side by side.
The above kind of mounting device can also be designed to receive one or more electrical devices side by side. If the mounting device has to receive several electrical devices, its length (i.e. its dimension in the longitudinal direction parallel to the trunking) is increased. In other words, the electrical device support and the skirt include openings of different lengths according to the number of electrical devices they are to receive.
The invention will be better understood and other advantages of the invention will become more clearly apparent in the light of the following description, which is given by way of example only and with reference to the accompanying drawings.